Charged particle beam apparatuses have many functions in a plurality of industrial fields, including, but not limited to, inspection of semiconductor devices during manufacturing, exposure systems for lithography, detecting devices and testing systems. Thus, there is a high demand for structuring and inspecting specimens within the micrometer and nanometer scale.
Micrometer and nanometer scale process control, inspection or structuring is often done with charged particle beams, e.g. electron beams, which are generated and focused in charged particle beam devices, such as electron microscopes or electron beam pattern generators. Charged particle beams offer superior spatial resolution compared to, e.g. photon beams, due to their short wavelengths.
The requirements of fast scanning are in particular important in applications of the manufacturing of semiconductors, where high throughput is essential. Such applications include electron beam inspection, defect review and critical dimension measurements.
Charged particle beam systems, such as a scanning electron microscope (SEM) can include detectors, such as scintillation detectors (e.g. P47 powders, YAG or YAP crystals or the like) or semiconductor detectors such as pin diodes, to detect charged particles, e.g. electrons and ions. They are usually arranged inside a vacuum environment. The vacuum contains residual contaminants like hydrocarbons outgassing from pumps or plastic components inside the vacuum chamber. These hydrocarbons adsorb on the surface of the detector leading to contamination of the detector.
Therefore, there is a need for a reduction of a detector contamination. It is desired to provide a means for reduction of contamination of a charged particle detector.